In a whole fruit juice extractor such as disclosed in commonly assigned U.S. Pat. Nos. 5,970,861; 5,992,311; 5,996,485; and 6,568,319, the disclosures which are hereby incorporated by reference in their entirety, the motion of the extractor cups and the orifice tube received within the strainer tube are each controlled by mechanical cams. Although the motions are separate, they are synchronized by having the cams located on a single camshaft. In this type of juice extractor, a drive cam (or cup cam) engages cam followers located on a cup support member, i.e., a cup beam. The cup beam cam followers are held in contact with the cams through the use of springs. Current machines include both mechanical springs and air springs. The mechanical springs are used as a safety mechanism to maintain the cup beam elevated or separated from non-moveable extractor cups if the air pressure fails.
There are a number of problems associated with this current design. As the speed of the juice extractor has increased over years of development, it has become necessary to increase the spring force necessary to hold the cam followers tightly to the drive cam. Mechanical springs, of course, were eventually replaced by air springs, and higher air pressure was necessary to prevent “knocking” of the cams corresponding to the separation of the cam from its follower. This additional force imports additional stresses on all members of the cam drive mechanism, causing premature failure of shafts and gears. In addition, the mechanical and air springs both require frequent replacement because of this increased force.